Tank construction



July 30, 1935. B. F. DIFFENDERFER 2,009,606

TANK CONSTRUCTION July 30, 1935. B. F. DIFFENDRFER 2,009,505

TANK CONSTRUCTION Filed April 18, 1933 2 Sheets-Sheet 2 Patented July3U, 1935 UNITED STATES PATENT OFFICE 4 Claims.

The present invention relates to tank structure and to the method ofmanufacture thereof, and is believed to have its best application withthe structure and manufacture of large tanks for storing corrosiveliquids and substances, the tanks being either open or closed at the topand suited to service under internal pressures greater than atmosphericpressure.

A purpose of the invention is to secure lightness and strength and topermit the convenient use, in Walls of tanks, of sheets of expensivecorrosion resistant materials, such as ferrous alloys like chrome steelor iron, stainless steel or iron, nickel steel or iron, etc., nonferrousmetals or d alloys like aluminum, tin, copper, nichrome, etc.,

and cladded metals like chrome clad, nickel clad, stainless steel clad,copper clad, alloy clad, etc. In some cases, carbon steels may be used.

A further purpose is to provide a composite cage for the effectivesupport of a thin sheet tank.

A further purpose is to secure easy access to the seams of a thin sheetexternally supported tank by making the external support in the form ofa composite cage, locating and/or making removable and adjustable thestructural members of the cage to wholly or partially disclose theseams.

In manufacture I usually make the inner tank walls of large relativelythin sheets of corrosionresistant material, as of stainless, or otherchrome, iron or steel, or other suitable material as set forth above,and the initial seams between the sheets that together make up the wallsof the inner tank may require repeated testing and subsequent fixing atone or more points before being satisfactorily perfect. 'Iherefore apurpose of the invention is to give easy access to the seams of theinner tank everywhere for a cut and try correction of the faultsoriginally present in the seams.

A further purpose is to secure a freedom from external structuralmembers along the corner portions of large thin sheet tanks, that is,along the common edges of the contiguous sides of the tank.

A further purpose is to externally support a thin metal cylinder tank bylongitudinal circumferentially spaced edgewise strips and compositecircumferential longitudinally spaced bands, making the respective bandsof arcuate sections intermediate and removably fastened together at thesuccessive strips.

A further purpose is to externally support the flat portions of a thinmetal tank with a. webbed grid open along the seams of the tank.

A further purpose is to obtain intimate supporting contact between arelatively light tank wall and a supporting cage.

A further purpose is to secure a close supporting iit between a closedthin metal tank and a 5 supporting composite external cage by expandingthe tank by fluid pressure into close engagement with the inwardlypresented surfaces of the cage while the cage is internally abnormallylarge because of untightened connections between its 10 members,subsequently contracting the cage by tightening its connections.

A further purpose is to provide different embodiments of the inventionfor respectively cylindrical and rectangular tanks.

A further purpose is to include a rectangular thin and preferablycorrugated sheet tank, within a structural framework, making theframework preferably comprise spaced frames of I-beams and removablecross connections, suitably angle 20 members.

Further purposes will appear in the specification and in the claims.

I have elected to show two only of the different forms of my invention,selecting forms however 25 that are practical and eilicient in operationand which well illustrate the principles involved.

Figures 1 and 2 illustrate a closed cylindrical tank and arerespectively side and end elevations of structure embodying a desirableform of my 30 invention.

Figures 3 and 4 illustrate an open rectangular tank, being viewscorresponding respectively to Figures 1 and 2, but showing anotherdesirable form of the invention.

Figure 5 is a detail section to enlarged scale taken upon the line 5-5of Figure 1.

Figure 6 is a detail section to enlarged scale taken upon the line 6-6of Figure 2.

Figure 'l is a detail section taken upon the line 40 1-1 of Figure 3.

Figure 8 is an enlarged scale detail section upon the line 8-8 of Figure3.

Figure 9 is a fragmentary section through an alternative form of jointwhich may be used in 45 my invention.

Like numerals refer to like parts in all figures.

Describing in illustration and not in limitation and referring to thedrawings:-

In the embodiment of Figures 1 and-2, a thin 50 sheet metal container I5is supported Within a supporting cage structure I6.

The container I5 will be usually for the storage of corrosive liquidsand therefore may be of large size, having its walls made up of anyrequisite 55 number of large sheets of corrosion-resistant material.

These sheets are suitably of stainless steel" or other chrome iron orsteel, of nickel steel, nickel chrome steel, aluminum, tin, copper,nichrome, or of chrome clad, nickel clad, "stainless steel clad, copperclad or other clad material, and therefore of a material very expensiveas compared to ordinary iron or steel of which the cage structure may bemade, for which reason the container walls are preferably f as lightgauge as may be consistent with the intended duty. In special casesordinary carbon steel may be used for the sheets.

The circumferential and end walls of the container I5 are seamedtogether along circumferential fianges Il of the end walls and may beeach made up of a plurality of large sheets seamed together.

In the illustration the end walls are alike, each made up of twosemi-circular pieces seamed together at I8 diametrally of the compositeend wall, and the circumferential wall is made up of a number of largerectangular sheets, the connecting seams extending in longitudinal andcircumferential directions, such seams being indicated at I9 and 20respectively.

The cage I6 is constructed for repeated and easy access to the seams,these seams being illustrated as circumferential seams at I'I, diametralend seams at I8 and relatively perpendicular longitudinal and arcuateseams I9 and 20 of the circumferential wall.

The cage includes circumferential and end portions to iit and externallysupport the corresponding portion of the container, and also to permitready and repeated access to the seams I1, I8, I9 and 20 of thecontainer.

'I'he circumferential portion of the cage comprises fiat bars 2|presented edgewise to the circumferential wall of the container alongthe length thereof and arcuate pieces 22 at longitudinal intervalsbetween the bars.

The arcuate pieces 22, in cooperation with connecting bolts 23 andintermediate portions of the flat bars form composite circumferentialbands at longitudinal intervals of thecontainer, the arcuate sections 22being individually readily removable for temporary access to any portionof any seam I9 normally crossed by the section. The ends of the arcuatepieces 22 are bent tangentially to the arcuate portions of the pieces at22', for convenient attachment to the bolts, and carry'openings 222through which the bolts pass.

'I'he composite bands of the cage are preferably located to avoidaltogether the arcuate seams 20 and the circumferential seams at II.

In the same way the flat bars 2| are located to altogether avoid thelongitudinally extending seams I9 of the container.

The seams I9, being of considerable length and transverse to thecomposite bands, must each cross a number of these bands, but do so atindividually removable sections 22 that may also be preferably outwardlyrecessed or outwardly depressed as at 24, Figure 5, to bridge the seam,permitting seam inspection under the section without removing thesection and, in case of need, easy access by removal of the section,such access being for the more easy correction of any fault of the seam.

'I'he arcuate pieces 22 may be either cast or pressed from fiat stockand may have individual modification as t0 form, to better suit localcharacteristics or needs of the container.

Thus the pieces over the seams I9 are preferably formed to Well clearthe seams, as shown at 24., Figure 5. The arcuate pieces 22 at any pipefittings 25 or 26 into the container are perforated, as at 21, Figure 5,to surround and pass the respective fittings. The arcuate pieces thatreceive the supporting legs 28 are provided with downwardly directedpillow or pad portions 29 suitably welded to the arcuate pieces 22 and'formed to flt the caps 30 of the vertically adjustable legs.

One of the cage ends is shown with manhole and manhole cover structureat 3| for admission into the interior of the container. Otherwise theends of the cage may be alike so that a description of one will suillcefor both.

As illustrated, each end member comprises a rigid unit made up of nearlysemi-circular webs or plates 32 and 33, inner and outer circular ribs 34and 35 and radial ribs 36, preferably secured together by welding.

The web or plate portions 32 and 33 are relatively spaced to disclosethe seam I8 and have an external circumference at 31 somewhat inwardlyfrom the outer circumference of the container, in order to give betteraccess to the circumferential seam at I'I.

The radial ribs 36 are located to register with the bars 2| of thecircumferential portion of the cage, being connected to the ends of thebars 2| by preferably removable knee members 38. These are bolted at 39and 48 respectively to the ribs 36 and the bars 2|.

The radial ribs 36 suitably extend radially outward a little distancebeyond the web members 32 and 33 and about to the circumference of theinner container.

In manufacture the cage is assembled at first somewhat loosely aroundthe container, leaving the bolts between the composite members of thecage initially untightened. I then subject the container to considerableinternal uid pressure, preferably tightening up the bolts of the cagewhile subjecting the container to the internal pressure, and therebysecure a very perfect fit between the cage and container.

The inner tank wall I5 is sufficiently flexible to expand slightly underthe fluid pressure, and, when the bolts 23 are tightened, the wall I 5is tightly gripped and supported by the cage structure.

'I'he seams of the container may be of a usual rivet and weld type andin manufacture such seams usually have initial faults, for which reasona container may have to be subjected to repeated testing withintermediate corrections of faults in one or more of the seams beforethe seams can be made everywhere perfect, and important features of thepresent invention are directed to the provisions for easy access to thedifferent seams in order to permit more easy correction of the initialfaults thereof. The ready access of the seams is also important topermit subsequent inspection of the tank at periodic intervals.

The circular ribs 34 and 35 are preferably outwardly recessed at 4Iwhere they pass the seam I8, to give ready access to this seam.

'I'he seam I8 is open to view and to access for correction of any faultthroughout its entire length, the bridging of the circular ribs 34 and35 over this seam being such as to permit adequate clearance for easycorrection of any faults at the same portions under these ribs.

Likewise the circumferential seams at I'I are accessible for correctionof any initial faults even at the portions of the seams directly underthe ends of the bars 2l and the knee members 38, since the knee membersand bars are both readily removable, and, even without removal of thebars, the bars have suitable bridging recesses at the seams.

The seams are also accessible for correction of any initial faults evenunder the bars 2 I, either by temporary removal of the bars or byproviding the bars with seam bridging recesses, as indicated at 42,Figure l, and the seams I9 are everywhere accessible, even under thearcuate plates 22, since these plates are readily removable.

While my invention finds its best use in a closed cylindrical tank,certain features thereof may be used also in tanks which are notcylindrical and in tanks which are open.

A container 43 of thin preferably corrugated sheet corrosion resistantmaterial, suitably stainless steel or other chrome iron or steel, isenclosed by and supported within a cage 44.

The container 43 will be usually of relatively large size, with thewalls and bottom therefore each made up of any requisite number of largesheets seamed together, the walls and bottom being themselves seamedtogether along the horizontal and vertical corners of the container.

The upper edges of the walls flange at 45 outwardly over and connect tothe top of the cage preferably upon a thin strip 46 of corrosionresistant material which serves to protect the top structural membersfrom direct contact with the corrosive liquid of the container.

The cage includes a grille work floor and grille work sides and ends,removably tied together into a cage having structural members, that maycross, but do not longitudinally cover, any one or more of the seams ofthe container, and the inner flat surfaces of the structural members ofthe cage being presentedI flat against the adjoining bottom, side or endof the container.

The cage floor comprises a structural grille work made up of angle sides41, angle ends 48, spaced I-beams 49 and short angles 50 atintervals'between the I-beams, with the top surfaces of all thesemembers in a common plane.

The side and end angles 41 and 48 present their vertical flangesoutwardly and downwardly, have their upper and horizontal flangesbeveled away at 5I and are removably fastened together by suitable angleclips 52 connecting the adjoining ends of the vertical flanges.

The I-beams 49 are at intervals between the angle ends 48 and havesuitably a total length equal to the distance between the verticalflanges of the side angles 41, with their top flanges cut away at theirends to pass the horizontal fianges of the angles 41. Suitable angleclips 53 riveted to the webs of the I-beams and preferably bolted to thevertical fianges of the angles 41 connect the I-beams 49 and side angles41 together.

The short angle members 50 have total lengths to t between the verticalanges of the opposing I-beams 49, and have theirflat top anges cut awayat the ends to permit presentation of the remaining portions of theirhorizontal top flanges between the corresponding flanges of the opposingI-beams. The short angles 50 are held at their ends (preferablyremovably) to the adjoining I-beams by angle clips 53'.

- The outside line of the rectangular container is at the inside line ofthe rectangular frame made by the angle members 41 and 48.

Spaced at successive intervals above the rectangular frame formed by theoutside angles 41 and 48 of the grille floor, I provide aheavyrectangular horizontal frame of side and end I-beams 54 and 55. asomewhat lighter rectangular horizontal frame of side and end I-beams 56and 51 and a relatively light top horizontal frame of side and endangles 58 and 59.

The side andend members of these frames are connected together at theirends, preferably removably by angle clips as already described, and theframes are connected to one another at horizontally spaced intervals byshort vertical angles 60, 6I and 62 respectively from the floor to theheavier I-bearn frame, between the heavier and lighter I-beam frames,and from the lighter I-beam frame to the angle frame around the top.

The angles 60, 6| and 82 are appropriately notched at their ends for apresentation of their inner faces into the common vertical plane of theinner faces of the frame members to which they connect, and are fastenedto place by suitable angle clips 63.

It will be seen that any one of the sides and ends of the cage may bereadily removable as a unit without disturbing the others.

Making the container of corrugated sheet permits relatively wide spacingbetween the vertical and horizontal structural members of the cage, sothat the seams are exposed to View except for short distances atrelatively widely spaced intervals where they are crossed by structuralmembers of the cage, that is, exposed to view, throughout nearly theirentire lengths.

The corrugations of the container plates are preferably longitudinal ofthe plates and the seams thereof along the edges of the plates mayinclude nesting overlaps of the corrugations of the adjoining sheets, asindicated at 64, Figure l7.

Where the seams are transverse to the corrugations, that is, where theseams are between the ends of adjoining-plates, the portions to overlapare preferably attened so as to remove the corrugations.-

In the seams across the bottom, the sheets are shown overlapping at 65and 66.

All of the seams may be Welded and/or riveted, and in manufacture theseams are usually made perfect only after repeated testing withintermediate elimination of the initial faults disclosed by the testing,and my external cage not only makes the tanks light and strong but alsomakes the seams open to inspection for leakages throughout their entirelengths, and provides easy access to seam faults needing correction.

The corrugation of the sheets makes the seams open for inspection evenwhere they cross structural members of the cage.

It will be evident that the inner tank wall is resilient, and that thecage supports the wall at intervals in two directions, longitudinallyand laterally.

It will also be evident that the type of joint between the sheets is notimportant to my invention. While I have generally shown lapped joints,the joints may be lapped or butted. Also, while I have generally shownjoints of the type which would be riveted, the joints may also beWelded. In Figure 9 I show a butt Welded joint, having Weld material at61 joining the sheets 63 and 69.

In view of my invention and disclosure, variations and modifications tomeet individual whim or particular need will doubtless become evident toothers skilled in the art, to obtain part or all of the benefits of myinvention without copying the structure shown, and I, therefore, claimall such in so far as they fall within the reasonable spirit and scopeof my invention.

Having thus described my invention, what I claim as new and desire tosecure by Letters Patent:

1. A tank comprising a. container made up of 4 a plurality of thin metalsheets seamed together Ymetal inner wall, a cage comprising a pluralityof members extending longitudinally of the inner wall in contact with itand circumferentially spaced around the inner wall and a plurality ofmembers extending circumferentially of the inner wall in contact with itand longitudinally spaced along the inner wall and means forcircumferentially tightening the circumferential members on the innerwall to insure rm support of the inner wall.

3. In a tank structure, a cylindrical container comprising a pluralityof thin metal sheets seamed together along contiguous edges and acomposite cage enclosing and externally tting the container andincluding bars edgewise along the cylinder and spaced from one anothercircumferentially around the cylinder and removable arcuate sectionsintermediate the bars at spaced intervals o1 the cylinder length and, incooperation with the bars and one another, forming composite bandsaround the cylinder.

4. In tank structure, a closed cylindrical container having walls thatinclude large thin sheets seamed together along contiguous edges and acage enclosing and externally iitting the container, the cage includingcircumferential and end portions spaced respectively longitudinallyinwardly and radially inwardly from the annular end corners of thecylinder and having, at spaced circumferential intervals, supportingconnections one to the other across the corners.

BENJAMIN F. DIFFENDERFER.

